The statements in this section merely provide background information related to the present disclosure and may or may not constitute prior art.
Hydrodynamic starting devices are often used in motor vehicles in order to improve the performance characteristics of the vehicle. One type of device includes the hydrodynamic launch or starting device. The hydrodynamic launch device is similar to a standard torque converter and generally includes three rotating elements: a pump, a turbine, and a stator. The pump is mechanically driven by a prime mover, such as an internal combustion engine or an electric motor. The turbine is mechanically coupled to a turbine shaft and is driven by fluid flow pumped by rotation of the pump. The stator is interposed between the pump and turbine and alters fluid flow returning from the turbine to the pump in order to multiply torque. In launch devices, the torque multiplication is only used at low gear speeds to improve the launch performance of the motor vehicle. Accordingly, the launch device is typically smaller than a standard torque converter.
While these launch devices are useful for their intended purpose, there is room in the art for a launch device that has efficient packaging, cost, and complexity while improving vehicle fuel efficiency by reducing the load on the engine while the motor vehicle is in idle.